A difficult problem of communication management is that of determining whether one channel of communication should be interrupted in order that another channel of communication be established. An executive may deem it annoying, inappropriate or unwise to interrupt an ongoing telephone or in-person conversation in order to dispatch instructions to his secretary or telephone operator concerning another incoming call particularly when the interruption turns out to be a less important matter which he can deal with at a later time. Alternatively, in some instances, the executive may want to be interrupted to attend to priority business. To avoid any discourtesy in the former case, it may be best to signal the secretary or operator in some silent manner parallel to the existing communication channel in order to avoid a discontinuity. The regular telephone hold and intercom is inadequate for this purpose as it produces an audible interruption and objectionable hiatus. Accordingly, a silent parallel communicating link is required. In the past it has been common for executivee to use some kind of buzzer system and code; but the buzzers aren't silent (which is annoying) and the language and messages capable of being so transmitted are limited. The primary object of the present invention is to provide a parallel communicating link for an executive that makes possible intelligent communication without disrupting the ongoing communication channel.